Autumn Foliage Color

The foliage colors at the Harvard Forest in Petersham, Massachusetts, are similar to those throughout the Northeast. The peak of the autumn colors at the Forest arrives between early and mid October, earlier than that in Boston and New York City by about two weeks, and later than central Vermont and New Hampshire by about two weeks. This site will introduce you to those changes and the science behind them.

This page was created in 2004 by Dr. John O’Keefe, Coordinator Emeritus of the Fisher Museum at Harvard Forest, and Dr. David Lee, Biological Sciences, Florida International University.

Autumn colors were different a century ago in southern New England, and they will likely continue to change during this century. These changes are largely due to human activity, including land-use changes, introduced pests and diseases, forest management, and climate change from fossil fuel emissions.